1 /* Maintain an RxRPC server socket to do AFS communications through
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
13 #include <net/af_rxrpc.h>
14 #include <rxrpc/packet.h>
18 static struct socket
*afs_socket
; /* my RxRPC socket */
19 static struct workqueue_struct
*afs_async_calls
;
20 static atomic_t afs_outstanding_calls
;
21 static atomic_t afs_outstanding_skbs
;
23 static void afs_wake_up_call_waiter(struct afs_call
*);
24 static int afs_wait_for_call_to_complete(struct afs_call
*);
25 static void afs_wake_up_async_call(struct afs_call
*);
26 static int afs_dont_wait_for_call_to_complete(struct afs_call
*);
27 static void afs_process_async_call(struct work_struct
*);
28 static void afs_rx_interceptor(struct sock
*, unsigned long, struct sk_buff
*);
29 static int afs_deliver_cm_op_id(struct afs_call
*, struct sk_buff
*, bool);
31 /* synchronous call management */
32 const struct afs_wait_mode afs_sync_call
= {
33 .rx_wakeup
= afs_wake_up_call_waiter
,
34 .wait
= afs_wait_for_call_to_complete
,
37 /* asynchronous call management */
38 const struct afs_wait_mode afs_async_call
= {
39 .rx_wakeup
= afs_wake_up_async_call
,
40 .wait
= afs_dont_wait_for_call_to_complete
,
43 /* asynchronous incoming call management */
44 static const struct afs_wait_mode afs_async_incoming_call
= {
45 .rx_wakeup
= afs_wake_up_async_call
,
48 /* asynchronous incoming call initial processing */
49 static const struct afs_call_type afs_RXCMxxxx
= {
51 .deliver
= afs_deliver_cm_op_id
,
52 .abort_to_error
= afs_abort_to_error
,
55 static void afs_collect_incoming_call(struct work_struct
*);
57 static struct sk_buff_head afs_incoming_calls
;
58 static DECLARE_WORK(afs_collect_incoming_call_work
, afs_collect_incoming_call
);
61 * open an RxRPC socket and bind it to be a server for callback notifications
62 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
64 int afs_open_socket(void)
66 struct sockaddr_rxrpc srx
;
67 struct socket
*socket
;
72 skb_queue_head_init(&afs_incoming_calls
);
74 afs_async_calls
= create_singlethread_workqueue("kafsd");
75 if (!afs_async_calls
) {
76 _leave(" = -ENOMEM [wq]");
80 ret
= sock_create_kern(AF_RXRPC
, SOCK_DGRAM
, PF_INET
, &socket
);
82 destroy_workqueue(afs_async_calls
);
83 _leave(" = %d [socket]", ret
);
87 socket
->sk
->sk_allocation
= GFP_NOFS
;
89 /* bind the callback manager's address to make this a server socket */
90 srx
.srx_family
= AF_RXRPC
;
91 srx
.srx_service
= CM_SERVICE
;
92 srx
.transport_type
= SOCK_DGRAM
;
93 srx
.transport_len
= sizeof(srx
.transport
.sin
);
94 srx
.transport
.sin
.sin_family
= AF_INET
;
95 srx
.transport
.sin
.sin_port
= htons(AFS_CM_PORT
);
96 memset(&srx
.transport
.sin
.sin_addr
, 0,
97 sizeof(srx
.transport
.sin
.sin_addr
));
99 ret
= kernel_bind(socket
, (struct sockaddr
*) &srx
, sizeof(srx
));
101 sock_release(socket
);
102 _leave(" = %d [bind]", ret
);
106 rxrpc_kernel_intercept_rx_messages(socket
, afs_rx_interceptor
);
114 * close the RxRPC socket AFS was using
116 void afs_close_socket(void)
120 sock_release(afs_socket
);
123 destroy_workqueue(afs_async_calls
);
125 ASSERTCMP(atomic_read(&afs_outstanding_skbs
), ==, 0);
126 ASSERTCMP(atomic_read(&afs_outstanding_calls
), ==, 0);
131 * note that the data in a socket buffer is now delivered and that the buffer
134 static void afs_data_delivered(struct sk_buff
*skb
)
137 _debug("DLVR NULL [%d]", atomic_read(&afs_outstanding_skbs
));
140 _debug("DLVR %p{%u} [%d]",
141 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
142 if (atomic_dec_return(&afs_outstanding_skbs
) == -1)
144 rxrpc_kernel_data_delivered(skb
);
149 * free a socket buffer
151 static void afs_free_skb(struct sk_buff
*skb
)
154 _debug("FREE NULL [%d]", atomic_read(&afs_outstanding_skbs
));
157 _debug("FREE %p{%u} [%d]",
158 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
159 if (atomic_dec_return(&afs_outstanding_skbs
) == -1)
161 rxrpc_kernel_free_skb(skb
);
168 static void afs_free_call(struct afs_call
*call
)
170 _debug("DONE %p{%s} [%d]",
171 call
, call
->type
->name
, atomic_read(&afs_outstanding_calls
));
172 if (atomic_dec_return(&afs_outstanding_calls
) == -1)
175 ASSERTCMP(call
->rxcall
, ==, NULL
);
176 ASSERT(!work_pending(&call
->async_work
));
177 ASSERT(skb_queue_empty(&call
->rx_queue
));
178 ASSERT(call
->type
->name
!= NULL
);
180 kfree(call
->request
);
185 * allocate a call with flat request and reply buffers
187 struct afs_call
*afs_alloc_flat_call(const struct afs_call_type
*type
,
188 size_t request_size
, size_t reply_size
)
190 struct afs_call
*call
;
192 call
= kzalloc(sizeof(*call
), GFP_NOFS
);
196 _debug("CALL %p{%s} [%d]",
197 call
, type
->name
, atomic_read(&afs_outstanding_calls
));
198 atomic_inc(&afs_outstanding_calls
);
201 call
->request_size
= request_size
;
202 call
->reply_max
= reply_size
;
205 call
->request
= kmalloc(request_size
, GFP_NOFS
);
211 call
->buffer
= kmalloc(reply_size
, GFP_NOFS
);
216 init_waitqueue_head(&call
->waitq
);
217 skb_queue_head_init(&call
->rx_queue
);
227 * clean up a call with flat buffer
229 void afs_flat_call_destructor(struct afs_call
*call
)
233 kfree(call
->request
);
234 call
->request
= NULL
;
240 * attach the data from a bunch of pages on an inode to a call
242 int afs_send_pages(struct afs_call
*call
, struct msghdr
*msg
, struct kvec
*iov
)
244 struct page
*pages
[8];
245 unsigned count
, n
, loop
, offset
, to
;
246 pgoff_t first
= call
->first
, last
= call
->last
;
251 offset
= call
->first_offset
;
252 call
->first_offset
= 0;
255 _debug("attach %lx-%lx", first
, last
);
257 count
= last
- first
+ 1;
258 if (count
> ARRAY_SIZE(pages
))
259 count
= ARRAY_SIZE(pages
);
260 n
= find_get_pages_contig(call
->mapping
, first
, count
, pages
);
261 ASSERTCMP(n
, ==, count
);
267 if (first
+ loop
>= last
)
270 msg
->msg_flags
= MSG_MORE
;
271 iov
->iov_base
= kmap(pages
[loop
]) + offset
;
272 iov
->iov_len
= to
- offset
;
275 _debug("- range %u-%u%s",
276 offset
, to
, msg
->msg_flags
? " [more]" : "");
277 msg
->msg_iov
= (struct iovec
*) iov
;
280 /* have to change the state *before* sending the last
281 * packet as RxRPC might give us the reply before it
282 * returns from sending the request */
283 if (first
+ loop
>= last
)
284 call
->state
= AFS_CALL_AWAIT_REPLY
;
285 ret
= rxrpc_kernel_send_data(call
->rxcall
, msg
,
290 } while (++loop
< count
);
293 for (loop
= 0; loop
< count
; loop
++)
294 put_page(pages
[loop
]);
297 } while (first
<= last
);
299 _leave(" = %d", ret
);
306 int afs_make_call(struct in_addr
*addr
, struct afs_call
*call
, gfp_t gfp
,
307 const struct afs_wait_mode
*wait_mode
)
309 struct sockaddr_rxrpc srx
;
310 struct rxrpc_call
*rxcall
;
315 _enter("%x,{%d},", addr
->s_addr
, ntohs(call
->port
));
317 ASSERT(call
->type
!= NULL
);
318 ASSERT(call
->type
->name
!= NULL
);
320 _debug("____MAKE %p{%s,%x} [%d]____",
321 call
, call
->type
->name
, key_serial(call
->key
),
322 atomic_read(&afs_outstanding_calls
));
324 call
->wait_mode
= wait_mode
;
325 INIT_WORK(&call
->async_work
, afs_process_async_call
);
327 memset(&srx
, 0, sizeof(srx
));
328 srx
.srx_family
= AF_RXRPC
;
329 srx
.srx_service
= call
->service_id
;
330 srx
.transport_type
= SOCK_DGRAM
;
331 srx
.transport_len
= sizeof(srx
.transport
.sin
);
332 srx
.transport
.sin
.sin_family
= AF_INET
;
333 srx
.transport
.sin
.sin_port
= call
->port
;
334 memcpy(&srx
.transport
.sin
.sin_addr
, addr
, 4);
337 rxcall
= rxrpc_kernel_begin_call(afs_socket
, &srx
, call
->key
,
338 (unsigned long) call
, gfp
);
340 if (IS_ERR(rxcall
)) {
341 ret
= PTR_ERR(rxcall
);
342 goto error_kill_call
;
345 call
->rxcall
= rxcall
;
347 /* send the request */
348 iov
[0].iov_base
= call
->request
;
349 iov
[0].iov_len
= call
->request_size
;
353 msg
.msg_iov
= (struct iovec
*) iov
;
355 msg
.msg_control
= NULL
;
356 msg
.msg_controllen
= 0;
357 msg
.msg_flags
= (call
->send_pages
? MSG_MORE
: 0);
359 /* have to change the state *before* sending the last packet as RxRPC
360 * might give us the reply before it returns from sending the
362 if (!call
->send_pages
)
363 call
->state
= AFS_CALL_AWAIT_REPLY
;
364 ret
= rxrpc_kernel_send_data(rxcall
, &msg
, call
->request_size
);
368 if (call
->send_pages
) {
369 ret
= afs_send_pages(call
, &msg
, iov
);
374 /* at this point, an async call may no longer exist as it may have
375 * already completed */
376 return wait_mode
->wait(call
);
379 rxrpc_kernel_abort_call(rxcall
, RX_USER_ABORT
);
380 rxrpc_kernel_end_call(rxcall
);
383 call
->type
->destructor(call
);
385 _leave(" = %d", ret
);
390 * handles intercepted messages that were arriving in the socket's Rx queue
391 * - called with the socket receive queue lock held to ensure message ordering
392 * - called with softirqs disabled
394 static void afs_rx_interceptor(struct sock
*sk
, unsigned long user_call_ID
,
397 struct afs_call
*call
= (struct afs_call
*) user_call_ID
;
399 _enter("%p,,%u", call
, skb
->mark
);
401 _debug("ICPT %p{%u} [%d]",
402 skb
, skb
->mark
, atomic_read(&afs_outstanding_skbs
));
404 ASSERTCMP(sk
, ==, afs_socket
->sk
);
405 atomic_inc(&afs_outstanding_skbs
);
408 /* its an incoming call for our callback service */
409 skb_queue_tail(&afs_incoming_calls
, skb
);
410 schedule_work(&afs_collect_incoming_call_work
);
412 /* route the messages directly to the appropriate call */
413 skb_queue_tail(&call
->rx_queue
, skb
);
414 call
->wait_mode
->rx_wakeup(call
);
421 * deliver messages to a call
423 static void afs_deliver_to_call(struct afs_call
*call
)
432 while ((call
->state
== AFS_CALL_AWAIT_REPLY
||
433 call
->state
== AFS_CALL_AWAIT_OP_ID
||
434 call
->state
== AFS_CALL_AWAIT_REQUEST
||
435 call
->state
== AFS_CALL_AWAIT_ACK
) &&
436 (skb
= skb_dequeue(&call
->rx_queue
))) {
438 case RXRPC_SKB_MARK_DATA
:
440 last
= rxrpc_kernel_is_data_last(skb
);
441 ret
= call
->type
->deliver(call
, skb
, last
);
445 call
->state
== AFS_CALL_AWAIT_REPLY
)
446 call
->state
= AFS_CALL_COMPLETE
;
449 abort_code
= RX_CALL_DEAD
;
452 abort_code
= RX_INVALID_OPERATION
;
455 abort_code
= RXGEN_CC_UNMARSHAL
;
456 if (call
->state
!= AFS_CALL_AWAIT_REPLY
)
457 abort_code
= RXGEN_SS_UNMARSHAL
;
459 rxrpc_kernel_abort_call(call
->rxcall
,
462 call
->state
= AFS_CALL_ERROR
;
465 afs_data_delivered(skb
);
468 case RXRPC_SKB_MARK_FINAL_ACK
:
470 call
->state
= AFS_CALL_COMPLETE
;
472 case RXRPC_SKB_MARK_BUSY
:
474 call
->error
= -EBUSY
;
475 call
->state
= AFS_CALL_BUSY
;
477 case RXRPC_SKB_MARK_REMOTE_ABORT
:
478 abort_code
= rxrpc_kernel_get_abort_code(skb
);
479 call
->error
= call
->type
->abort_to_error(abort_code
);
480 call
->state
= AFS_CALL_ABORTED
;
481 _debug("Rcv ABORT %u -> %d", abort_code
, call
->error
);
483 case RXRPC_SKB_MARK_NET_ERROR
:
484 call
->error
= -rxrpc_kernel_get_error_number(skb
);
485 call
->state
= AFS_CALL_ERROR
;
486 _debug("Rcv NET ERROR %d", call
->error
);
488 case RXRPC_SKB_MARK_LOCAL_ERROR
:
489 call
->error
= -rxrpc_kernel_get_error_number(skb
);
490 call
->state
= AFS_CALL_ERROR
;
491 _debug("Rcv LOCAL ERROR %d", call
->error
);
501 /* make sure the queue is empty if the call is done with (we might have
502 * aborted the call early because of an unmarshalling error) */
503 if (call
->state
>= AFS_CALL_COMPLETE
) {
504 while ((skb
= skb_dequeue(&call
->rx_queue
)))
506 if (call
->incoming
) {
507 rxrpc_kernel_end_call(call
->rxcall
);
509 call
->type
->destructor(call
);
518 * wait synchronously for a call to complete
520 static int afs_wait_for_call_to_complete(struct afs_call
*call
)
525 DECLARE_WAITQUEUE(myself
, current
);
529 add_wait_queue(&call
->waitq
, &myself
);
531 set_current_state(TASK_INTERRUPTIBLE
);
533 /* deliver any messages that are in the queue */
534 if (!skb_queue_empty(&call
->rx_queue
)) {
535 __set_current_state(TASK_RUNNING
);
536 afs_deliver_to_call(call
);
541 if (call
->state
>= AFS_CALL_COMPLETE
)
544 if (signal_pending(current
))
549 remove_wait_queue(&call
->waitq
, &myself
);
550 __set_current_state(TASK_RUNNING
);
553 if (call
->state
< AFS_CALL_COMPLETE
) {
554 _debug("call incomplete");
555 rxrpc_kernel_abort_call(call
->rxcall
, RX_CALL_DEAD
);
556 while ((skb
= skb_dequeue(&call
->rx_queue
)))
560 _debug("call complete");
561 rxrpc_kernel_end_call(call
->rxcall
);
563 call
->type
->destructor(call
);
565 _leave(" = %d", ret
);
570 * wake up a waiting call
572 static void afs_wake_up_call_waiter(struct afs_call
*call
)
574 wake_up(&call
->waitq
);
578 * wake up an asynchronous call
580 static void afs_wake_up_async_call(struct afs_call
*call
)
583 queue_work(afs_async_calls
, &call
->async_work
);
587 * put a call into asynchronous mode
588 * - mustn't touch the call descriptor as the call my have completed by the
591 static int afs_dont_wait_for_call_to_complete(struct afs_call
*call
)
598 * delete an asynchronous call
600 static void afs_delete_async_call(struct work_struct
*work
)
602 struct afs_call
*call
=
603 container_of(work
, struct afs_call
, async_work
);
613 * perform processing on an asynchronous call
614 * - on a multiple-thread workqueue this work item may try to run on several
615 * CPUs at the same time
617 static void afs_process_async_call(struct work_struct
*work
)
619 struct afs_call
*call
=
620 container_of(work
, struct afs_call
, async_work
);
624 if (!skb_queue_empty(&call
->rx_queue
))
625 afs_deliver_to_call(call
);
627 if (call
->state
>= AFS_CALL_COMPLETE
&& call
->wait_mode
) {
628 if (call
->wait_mode
->async_complete
)
629 call
->wait_mode
->async_complete(call
->reply
,
634 rxrpc_kernel_end_call(call
->rxcall
);
636 if (call
->type
->destructor
)
637 call
->type
->destructor(call
);
639 /* we can't just delete the call because the work item may be
641 PREPARE_WORK(&call
->async_work
, afs_delete_async_call
);
642 queue_work(afs_async_calls
, &call
->async_work
);
649 * empty a socket buffer into a flat reply buffer
651 void afs_transfer_reply(struct afs_call
*call
, struct sk_buff
*skb
)
653 size_t len
= skb
->len
;
655 if (skb_copy_bits(skb
, 0, call
->buffer
+ call
->reply_size
, len
) < 0)
657 call
->reply_size
+= len
;
661 * accept the backlog of incoming calls
663 static void afs_collect_incoming_call(struct work_struct
*work
)
665 struct rxrpc_call
*rxcall
;
666 struct afs_call
*call
= NULL
;
669 while ((skb
= skb_dequeue(&afs_incoming_calls
))) {
672 /* don't need the notification */
676 call
= kzalloc(sizeof(struct afs_call
), GFP_KERNEL
);
678 rxrpc_kernel_reject_call(afs_socket
);
682 INIT_WORK(&call
->async_work
, afs_process_async_call
);
683 call
->wait_mode
= &afs_async_incoming_call
;
684 call
->type
= &afs_RXCMxxxx
;
685 init_waitqueue_head(&call
->waitq
);
686 skb_queue_head_init(&call
->rx_queue
);
687 call
->state
= AFS_CALL_AWAIT_OP_ID
;
689 _debug("CALL %p{%s} [%d]",
690 call
, call
->type
->name
,
691 atomic_read(&afs_outstanding_calls
));
692 atomic_inc(&afs_outstanding_calls
);
695 rxcall
= rxrpc_kernel_accept_call(afs_socket
,
696 (unsigned long) call
);
697 if (!IS_ERR(rxcall
)) {
698 call
->rxcall
= rxcall
;
708 * grab the operation ID from an incoming cache manager call
710 static int afs_deliver_cm_op_id(struct afs_call
*call
, struct sk_buff
*skb
,
713 size_t len
= skb
->len
;
714 void *oibuf
= (void *) &call
->operation_ID
;
716 _enter("{%u},{%zu},%d", call
->offset
, len
, last
);
718 ASSERTCMP(call
->offset
, <, 4);
720 /* the operation ID forms the first four bytes of the request data */
721 len
= min_t(size_t, len
, 4 - call
->offset
);
722 if (skb_copy_bits(skb
, 0, oibuf
+ call
->offset
, len
) < 0)
724 if (!pskb_pull(skb
, len
))
728 if (call
->offset
< 4) {
730 _leave(" = -EBADMSG [op ID short]");
733 _leave(" = 0 [incomplete]");
737 call
->state
= AFS_CALL_AWAIT_REQUEST
;
739 /* ask the cache manager to route the call (it'll change the call type
741 if (!afs_cm_incoming_call(call
))
744 /* pass responsibility for the remainer of this message off to the
745 * cache manager op */
746 return call
->type
->deliver(call
, skb
, last
);
750 * send an empty reply
752 void afs_send_empty_reply(struct afs_call
*call
)
759 iov
[0].iov_base
= NULL
;
765 msg
.msg_control
= NULL
;
766 msg
.msg_controllen
= 0;
769 call
->state
= AFS_CALL_AWAIT_ACK
;
770 switch (rxrpc_kernel_send_data(call
->rxcall
, &msg
, 0)) {
772 _leave(" [replied]");
777 rxrpc_kernel_abort_call(call
->rxcall
, RX_USER_ABORT
);
779 rxrpc_kernel_end_call(call
->rxcall
);
781 call
->type
->destructor(call
);
789 * send a simple reply
791 void afs_send_simple_reply(struct afs_call
*call
, const void *buf
, size_t len
)
798 iov
[0].iov_base
= (void *) buf
;
799 iov
[0].iov_len
= len
;
804 msg
.msg_control
= NULL
;
805 msg
.msg_controllen
= 0;
808 call
->state
= AFS_CALL_AWAIT_ACK
;
809 switch (rxrpc_kernel_send_data(call
->rxcall
, &msg
, len
)) {
811 _leave(" [replied]");
816 rxrpc_kernel_abort_call(call
->rxcall
, RX_USER_ABORT
);
818 rxrpc_kernel_end_call(call
->rxcall
);
820 call
->type
->destructor(call
);
828 * extract a piece of data from the received data socket buffers
830 int afs_extract_data(struct afs_call
*call
, struct sk_buff
*skb
,
831 bool last
, void *buf
, size_t count
)
833 size_t len
= skb
->len
;
835 _enter("{%u},{%zu},%d,,%zu", call
->offset
, len
, last
, count
);
837 ASSERTCMP(call
->offset
, <, count
);
839 len
= min_t(size_t, len
, count
- call
->offset
);
840 if (skb_copy_bits(skb
, 0, buf
+ call
->offset
, len
) < 0 ||
841 !pskb_pull(skb
, len
))
845 if (call
->offset
< count
) {
847 _leave(" = -EBADMSG [%d < %zu]", call
->offset
, count
);
850 _leave(" = -EAGAIN");